1. Field of the Invention
The present invention relates to a wiper assembly capable of adjusting a wiping angle, and more particularly, to a wiper assembly capable of adjusting a wiping angle by employing an auxiliary motor to adjust the operating angle of drive arms in accordance with the change of a wiper operating mode (high-speed operating mode or low-speed operating mode) so that the wiping angle is properly adjusted in response to the operating condition of wiper assembly.
2. Description of the Prior Art
In a motor vehicle, a front windshield is provided to prevent the inflow of precipitation and/or wind while driving. When dirt and other forms of debris are accumulated on the front windshield, a driver would have a trouble in securing a clean visual field through the windshield. Especially, when driving in a region where in rain or snowfall is occurring, the precipitation accumulating on the front windshield should be rapidly removed in order to secure a clean visual field.
Thus, a motor vehicle is provided with a wiper assembly for securing a clean visual field, capable of removing dirt and/or precipitation accumulating on the front windshield.
FIG. 1 is a perspective view showing a conventional wiper assembly.
As shown in FIG. 1, the conventional wiper assembly comprises a wiper motor (2), a crank arm (4), a drive arms (14, 16), a first connecting rod (6) disposed between the crank arm (4) and the drive arm (14) for converting a rotating motion of the crank arm into a reciprocal motion of the drive arm (14), and a second connecting rod (8) transferring the driving force of the wiper motor to a pivot (10) by means of the drive arm (16).
As shown in FIG. 2, a wiper arm (18, 18xe2x80x2) and a wiper blade are connected to the pivot (10) and (12), respectively.
In the above arrangement, beginning with the crank arm (4) rotated by the wiper motor (2), the driving force of the wiper motor (2) is transferred to the drive arms (14) and (16) by means of the first connecting road (6) and the second connecting rod (8). Subsequently, the pivots (12) and (10) connected to the drive arms (14) and (16), are rotated, whereby the wiper arms (18, 18xe2x80x2) and wiper blades connected to the pivots are rotated for removing dirt and precipitation being accumulated on the front windshield. In FIG. 1, a1 and a2 indicate the wiping angle of a conventional wiper assembly.
In the above-described conventional wiper assembly, the wiper arms normally reciprocate within the predetermined wiping angles (a1, a2) in low-speed operating mode of the wiper assembly. If the wiper assembly, however, is operated in high-speed operating mode, the wiping angle of the wiper arms exceeds the predetermined angles (a1, a2) due to the inertial force incurred by high-speed operation resulting in the interference with front pillars or a cowl cover.
Furthermore, in the high-speed operating mode, the noise generated from a wiper blade when the direction of the wiper arm is reversed, is increased due to the increase of a wiping angle and inertial force. As a result, the discontent against the noise is frequently voiced among customers.
In view of the foregoing state of the prior art, the present invention provides a wiper assembly capable of adjusting a wiping angle, which adjust a wiping angle in high-speed operation mode of the wiper assembly in order to not only prevent a wiper blade from interfering with front pillars or a cowl cover, but also to decrease reversion-noise generated from the wiper blades.
In order to achieve the above performance, a wiper assembly capable of adjusting a wiping angle according to the present invention, comprises a main frame mounted on the body of a vehicle by means of a plurality of fixing holes, a wiper motor installed to the main frame, the first connecting rod and the second connecting rod transferring the driving force of the motor to drive arms, wiper arms and wiper blades connected to the drive arms through the pivots, is characterized by an auxiliary motor mounted on the frame, having a variable crankshaft for moving the center axis of the variable crankshaft from position P1 to position P2, and a variable link of which the first end is operatively coupled to the one end of the variable crankshaft and the second end is coupled to the first connecting rod, the second connecting rod coupled to one drive arm, and a link rod coupled to the other drive arm, wherein the variable link moves the location of drive arms from P1xe2x80x2 to P2xe2x80x2 or from P2xe2x80x2 to P1xe2x80x2 in accordance with the movement of a pivot (C1 or C2) occurred by operating of the variable crank.